What Your DNA Says About Medieval History – “A new study uses genetic data from living people to trace millennia-old migration patterns…. [M]uch of what Capelli and his colleagues discovered meshed with what historians already knew. For example, among northern Europeans, highest rate of admixing took place ‘around the late first millennium C.E., a time known to have involved significant upheaval in Europe,’ while admixture between north African and southern European populations was dated to a time span ‘consistent with migrations associated with the Arabic Conquest of the Iberian peninsula.’ But there were surprises, too. Most notably, Capelli and his colleagues discovered evidence for an influx of Mongolians into Europe that predated the reign of Ghengis Khan.” – orig. research article: The Role of Recent Admixture in Forming the Contemporary West Eurasian Genomic Landscape.

Inuit Study Adds Twist to Omega-3 Fatty Acids’ Health Story – “A study published on Thursday in the journal Science reported that the ancestors of the Inuit evolved unique genetic adaptations for metabolizing omega-3s and other fatty acids. Those gene variants had drastic effects on Inuit’s bodies, reducing their heights and weights. Rasmus Nielsen, a geneticist at the University of California, Berkeley, and an author of the new study, said that the discovery raised questions about whether omega-3 fats really were protective for everyone, despite decades of health advice. ‘The same diet may have different effects on different people,’ he said…. The researchers found several genetic variants at different locations in the genome that were unusually common in the Inuit, compared with people in Europe or China. Several of these variations occurred within a cluster of genes that direct construction of enzymes called fatty acid desaturases. (The genes are called FADS, for short….) Even more intriguing was the fact that one of these gene variants was present in almost every Inuit in the study. It is much less common in other populations: About a quarter of Chinese people have it, compared with just 2 percent of Europeans. Natural selection is the only known way this gene variant could have become so common in the Inuit. Dr. Nielsen said this adaptation might have arisen as long ago as 20,000 years, when the ancestors of the Inuit were living in the Beringia region, which straddles Alaska and Siberia…. The adaptation did more than just change blood levels of fatty acids, the scientists found. Inuit who carried two copies of the variant gene were on average an inch shorter and 10 pounds lighter than those without a copy.” – orig. research article: Greenlandic Inuit show genetic signatures of diet and climate adaptation. see also Your Genes Are What You Eat from razib.

5 key facts about the nuclear DNA from Sima de los Huesos – “If confirmed, the results will push back the H. sapiens-H. neanderthalensis ancestor beyond 400 KYA. Meyer suggested that the ancestors of H. sapiens could have diverged from the branch leading to neandertals and denisovans 550 K to 765 K years ago. It may be possible that H. sapiens evolved in western Eurasia and later migrated back into Africa. The fossils from Europe, Asia and Africa in the 400 Ka. period are physically very diverse and may represent multiple species, only one of which could be the ancestor of today’s humans. For example, Chris Stringer thinks it may be needed to look at Homo antecessor and not Homo heidelbergensis as our last common ancestor with neandertals.”

Origins, admixture and founder lineages in European Roma – “We found a set of founder lineages, present in the Roma and virtually absent in the non-Roma, for the maternal (H7, J1b3, J1c1, M18, M35b, M5a1, U3, and X2d) and paternal (I-P259, J-M92, and J-M67) genomes. This lineage classification allows us to identify extensive gene flow from non-Roma to Roma groups, whereas the opposite pattern, although not negligible, is substantially lower (up to 6.3%). Finally, the exact haplotype matching analysis of both uniparental lineages consistently points to a Northwestern origin of the proto-Roma population within the Indian subcontinent.”

Green Arabia’s key role in human evolution – “Scientists have been illuminating the vital role played by the Arabian Peninsula in humankind’s exodus from Africa. Far from being a desert, the region was once covered by lush vegetation and criss-crossed by rivers, providing rich hunting grounds for our ancestors.”

Sons of the Soil, Migrants, and Civil War – “In nearly a third of ethnic civil wars since 1945, the conflict develops between members of a regional ethnic group that considers itself to be the indigenous “sons of the soil” and recent migrants from other parts of the country.” – h/t whyvert!

Ancient campfires show early population numbers [in australia] – “ANU archaeologist Alan Williams used radio carbon dating technology to examine charcoal dates from more than 1000 prehistoric campfires and based on this he says populations appear to have increased steadily until 25,000 years ago…. After this initial increase, he says, population levels remained steady or even declined from 25,000 years ago, during the more arid Last Glacial Maximum (25,000 to 13,000 years ago) when temperatures were about ten degrees cooler…. Campfire numbers began to grow again 13,000 years ago when the northern wet season re-emerged.”

bonus bonus bonus: this year’s ig nobel mathematics prize went to the authors of The Case of Moulay Ismael – Fact or Fancy? – “Textbooks on evolutionary psychology and biology cite the case of the Sharifian Emperor of Morocco, Moulay Ismael the Bloodthirsty (1672–1727) who was supposed to have sired 888 children. This example for male reproduction has been challenged and led to a still unresolved discussion. The scientific debate is shaped by assumptions about reproductive constraints which cannot be tested directly — and the figures used are sometimes arbitrary. Therefore we developed a computer simulation which tests how many copulations per day were necessary to reach the reported reproductive outcome…. The results indicate that Moulay Ismael could have achieved this high reproductive success. A comparison of the three conception models highlights the necessity to consider female sexual habits when assessing fertility across the cycle. We also show that the harem size needed is far smaller than the reported numbers.” (~_^)

Although mutation rates (per base pair) have clearly changed across primate evolution, many analyses continue to assume that all present-day human populations have the same mutation rates. Recently, William Amos analyzed 1000 Genomes Project and Complete Genomics sequences and found evidence of significantly higher divergence rates on African than on non-African lineages since separation (W. Amos, PLoS One 4, e63048). The detected pattern was strongest in genomic regions of high polymorphism rate, a pattern that the author hypothesized was due to ‘heterozygote instability’, whereby gene conversion events surrounding heterozygous sites increase the mutation rate. To further test this observation, we measured the relative accumulation of mutations in lineages drawn from two different populations, using 25 deep genome sequences generated according to the same experimental protocol using the Illumina technology. We carried out pairwise comparisons of five sub-Saharan African (Dinka, Mandenka, Mbuti, San, Yoruba) and eight Non-African populations (Australian, Dai, French, Han, Karitiana, Mixe, Papuan, Sardinian) on all divergent sites. We observed statistically significant differences in the relative accumulation of mutations for many pairs of African and Non-African populations. Among the strongest differences is significantly more lineage-specific mutations in Mbuti than in Han Chinese (R=1.044, standard error (SE) =0.0015). On average, we observed about 1% more mutations on African lineages compared to Non-African lineages. We also observed some significant differences across non-African populations, with the Han Chinese who have experienced extreme expansions in population size associated with agriculture having more mutations than the Karitiana, a hunter-gatherer population from Amazonia who did not experience such expansions (R=1.015, SE=0.0014). The results are consistent across both European and African segments of the human reference sequence, so are not an artifact of reference sequence bias. Taken together, these results support the view that per-base pair mutation rates may be dynamically and substantially changing across humans.

I Don’t Feel Your Pain – “A recent study shows that people, including medical personnel, assume black people feel less pain than white people…. In each experiment, the researchers found that white participants, black participants, and nurses and nursing students assumed that blacks felt less pain than whites.” – original research article.

Accelerating adaptive evolution in humans – “In my last post, I noted R.A. Fisher’s argument that a larger population leads to more mutations and greater potential for adaptive evolution. As human populations have undergone massive growth over recent tens of thousands of years, we would expect the evidence of this population growth to show in our genomes. In this post, I point to a couple of papers that look at this evidence.” – from jason collins.

How Long Can You Wait to Have a Baby? – “[M]illions of women are being told when to get pregnant based on statistics from a time before electricity, antibiotics, or fertility treatment. Most people assume these numbers are based on large, well-conducted studies of modern women, but they are not.”

Grandparents effect spotted in British class system – “Children’s eventual position in Britain’s class system is closely linked to that of their grandparents, not just their parents, academics say. And where parents have ‘dropped down’ the socio-economic ladder, the so-called ‘grandparents effect’ often pulls them back up, research suggests…. [A]mong men with both parents and grandparents in the highest socio-economic group, 80% stayed in those positions when they were adults. But among men whose parents had been upwardly mobile, only 61% stayed in the group they had been born in to.” – don’t they mean the “regression to the mean effect’? – via jason collins.

Clues in the Cycle of Suicide – “Every year, suicide peaks with the tulips and lilacs — increasing roughly 15 percent over the annual average to create one of psychiatry’s most consistent epidemiological patterns. It may seem perverse that the period of spring and early summer … should contain ‘a capacity for self-murder that winter less often has.’ Yet it does.”

Sardinian family’s tip for a long life: minestrone – and good longevity genes! (~_^) – “Luca Deiana, a professor of clinical biochemistry at the university of Sassari in Sardinia, who has studied some 2500 centenarians on the island since 1996, was quoted by Corriere della Sera at the time as saying the longevity of local inhabitants was influenced by genetics along with environmental, nutritional and lifestyle habits.”

Mysterious Pair Buried With Flowers — Oldest Example Yet – “The pair — an adult male and an adolescent of undetermined sex — belonged to the primitive Natufian culture, which flourished between 15,000 and 11,600 years ago in an area that is now Israel, Jordan, Lebanon, and Syria.”